css3 footer tutorial ( kicking boxes )

Hello everyone!!i'm Alex and just finished the html & css tutorial, html5 tutorial and now css3 footer tutorial.First question: where can i find the code files on your tutorials?Second question: Watching the CSS3 footer tut i was typing the css code and run it but the buttons when i hover on them ( for ex. on the first button ) all the buttons on the right of it disappears and the current button take all over the place.( a.k.a. there are no stable at their position)also opacity doesn't work.Here is my code: